In recent years, considerable effort has been expended in reducing the combustion inefficiency of internal combustion engines, and reducing particulate matter produced by those engines, as well as gaseous hydrocarbon pollutants.
One of the innovations that has been developed to reduce the pollution caused by internal combustion engines, and particularly by diesel engines, is the diesel particulate filter. A diesel particulate filter collects microscopic particulate matter that is suspended in the exhaust gas issuing from the diesel engine.
Diesel particulate filters must be periodically cleaned. This cleaning is typically done by thermally cycling the diesel particulate filter to incinerate the diesel particulate matter at elevated temperatures, typically on the order of 600° C. Diesel fuel is injected into the exhaust gas leaving the diesel engine to spontaneously combust, thereby elevating the gas temperature and cause it to combust the particulate matter in the diesel particulate filter.
One problem that arises from this process is the periodic elevated temperatures that the diesel particulate filter experiences when it is thermally cycled and cleaned. In normal use it is cool. During the normal mode of operation, combustible material may settle on the now-cool surface of the diesel particulate filter and form a substantial layer that can autocombust if the filter temperature increases to its 600° C. recycling temperature.
What is needed, therefore, is a different arrangement for preventing crop dust from building up on the diesel particulate filter. It is an object of this invention to provide such an arrangement.